| % SCTP wrapper behavior, used by M2PA/M2UA/M3UA/SUA |
| |
| % (C) 2011-2012 by Harald Welte <laforge@gnumonks.org> |
| % |
| % All Rights Reserved |
| % |
| % This program is free software; you can redistribute it and/or modify |
| % it under the terms of the GNU Affero General Public License as |
| % published by the Free Software Foundation; either version 3 of the |
| % License, or (at your option) any later version. |
| % |
| % This program is distributed in the hope that it will be useful, |
| % but WITHOUT ANY WARRANTY; without even the implied warranty of |
| % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| % GNU General Public License for more details. |
| % |
| % You should have received a copy of the GNU Affero General Public License |
| % along with this program. If not, see <http://www.gnu.org/licenses/>. |
| |
| -module(sctp_core). |
| -author('Harald Welte <laforge@gnumonks.org>'). |
| -behaviour(gen_fsm). |
| |
| -include_lib("kernel/include/inet_sctp.hrl"). |
| -include("osmo_util.hrl"). |
| |
| -export([start_link/1]). |
| |
| -export([init/1, terminate/3, code_change/4, handle_event/3, handle_info/3]). |
| |
| -export([behaviour_info/1]). |
| |
| % FSM states: |
| -export([idle/2, associating/2, established/2]). |
| |
| behaviour_info(callbacks) -> |
| gen_fsm:behaviour_info(callbacks) ++ [{rx_sctp, 4}, {mtp_xfer, 2}, {state_change, 2}]; |
| behaviour_info(Other) -> |
| gen_fsm:behaviour_info(Other). |
| |
| % Loop Data |
| -record(sctp_state, { |
| role, % passive | active |
| state, % idle | associating | established |
| user_pid, |
| sctp_remote_ip, |
| sctp_remote_port, |
| sctp_local_port, |
| sctp_sock, |
| sctp_assoc_id, |
| module, % callback module |
| ext_state % state of the callback module |
| }). |
| |
| start_link(InitOpts) -> |
| gen_fsm:start_link(?MODULE, InitOpts, [{debug, [trace]}]). |
| |
| reconnect_sctp(L = #sctp_state{sctp_remote_ip = Ip, sctp_remote_port = Port, sctp_sock = Sock}) -> |
| io:format("SCTP Reconnect ~p:~p~n", [Ip, Port]), |
| timer:sleep(1*1000), |
| InitMsg = #sctp_initmsg{num_ostreams = 2, max_instreams = 2}, |
| case gen_sctp:connect_init(Sock, Ip, Port, [{active, once}, {reuseaddr, true}, |
| {sctp_initmsg, InitMsg}]) of |
| ok -> |
| ok; |
| {error, Error } -> |
| io:format("SCTP Error ~p, reconnecting~n", [Error]), |
| reconnect_sctp(L) |
| end. |
| |
| init(InitOpts) -> |
| OpenOptsBase = [{active, once}, {reuseaddr, true}], |
| Module = proplists:get_value(module, InitOpts), |
| ModuleArgs = proplists:get_value(module_args, InitOpts), |
| LocalPort = proplists:get_value(sctp_local_port, InitOpts), |
| Role = proplists:get_value(sctp_role, InitOpts), |
| case LocalPort of |
| undefined -> |
| OpenOpts = OpenOptsBase; |
| _ -> |
| OpenOpts = OpenOptsBase ++ [{port, LocalPort}] |
| end, |
| {ok, SctpSock} = gen_sctp:open(OpenOpts), |
| case Module:init(ModuleArgs) of |
| {ok, ExtState} -> |
| LoopDat = #sctp_state{role = Role, sctp_sock = SctpSock, |
| user_pid = proplists:get_value(user_pid, InitOpts), |
| ext_state = ExtState, module = Module, |
| sctp_remote_ip = proplists:get_value(sctp_remote_ip, InitOpts), |
| sctp_remote_port = proplists:get_value(sctp_remote_port, InitOpts), |
| sctp_local_port = LocalPort}, |
| case Role of |
| active -> |
| gen_fsm:send_event(self(), osmo_util:make_prim('M','SCTP_ESTABLISH',request)); |
| _ -> |
| ok |
| end, |
| {ok, idle, LoopDat}; |
| Default -> |
| {error, {module_returned, Default}} |
| end. |
| |
| terminate(Reason, State, LoopDat) -> |
| io:format("Terminating ~p (Reason: ~p)~n", [?MODULE, Reason]), |
| Module = LoopDat#sctp_state.module, |
| gen_sctp:close(LoopDat#sctp_state.sctp_sock), |
| Module:terminate(Reason, State, LoopDat#sctp_state.ext_state). |
| |
| code_change(OldVsn, StateName, LoopDat, Extra) -> |
| Module = LoopDat#sctp_state.module, |
| case Module:code_change(OldVsn, StateName, LoopDat#sctp_state.ext_state, Extra) of |
| {ok, ExtState} -> |
| {ok, StateName, LoopDat#sctp_state{ext_state = ExtState}}; |
| Other -> |
| Other |
| end. |
| |
| % Helper function to send data to the SCTP peer |
| send_sctp_to_peer(LoopDat, PktData, StreamId, Ppid) when is_binary(PktData) -> |
| #sctp_state{sctp_sock = Sock, sctp_assoc_id = Assoc} = LoopDat, |
| SndRcvInfo = #sctp_sndrcvinfo{assoc_id = Assoc, ppid = Ppid, stream = StreamId}, |
| gen_sctp:send(Sock, SndRcvInfo, PktData). |
| |
| send_prim_to_user(LoopDat, Prim) when is_record(LoopDat, sctp_state), is_record(Prim, primitive) -> |
| %#m3ua_state{user_fun = Fun, user_args = Args} = LoopDat, |
| %Fun(Prim, Args). |
| UserPid = LoopDat#sctp_state.user_pid, |
| UserPid ! Prim. |
| |
| |
| handle_event(Event, State, LoopDat) -> |
| Module = LoopDat#sctp_state.module, |
| io:format("Unknown Event ~p in state ~p~n", [Event, State]), |
| case Module:handle_event(Event, State, LoopDat#sctp_state.ext_state) of |
| {next_state, State, ExtState} -> |
| {next_state, State, LoopDat#sctp_state{ext_state = ExtState}} |
| end. |
| |
| |
| handle_info({sctp, Socket, _RemoteIp, _RemotePort, {ANC, SAC}}, |
| State, LoopDat) when is_record(SAC, sctp_assoc_change) -> |
| io:format("SCTP Assoc Change ~p ~p~n", [ANC, SAC]), |
| #sctp_assoc_change{state = SacState, outbound_streams = _OutStreams, |
| inbound_streams = _InStreams, assoc_id = AssocId} = SAC, |
| if |
| SacState == comm_up; |
| SacState == restart -> |
| case State of |
| associating -> |
| NewState = established, |
| Spec = confirm; |
| _ -> |
| NewState = State, |
| Spec = indication |
| end, |
| % primitive to the user |
| send_prim_to_user(LoopDat, osmo_util:make_prim('M','SCTP_ESTABLISH',Spec)); |
| SacState == comm_lost -> |
| case State of |
| releasing -> |
| Spec = confirm; |
| _ -> |
| Spec = indication |
| end, |
| send_prim_to_user(LoopDat, osmo_util:make_prim('M','SCTP_RELEASE',Spec)), |
| case LoopDat#sctp_state.role of |
| active -> |
| NewState = associating, |
| reconnect_sctp(LoopDat); |
| _ -> |
| NewState = idle |
| end; |
| SacState == addr_unreachable -> |
| case LoopDat#sctp_state.role of |
| active -> |
| NewState = associating, |
| reconnect_sctp(LoopDat); |
| _ -> |
| NewState = idle |
| end |
| end, |
| inet:setopts(Socket, [{active, once}]), |
| next_state(State, NewState, LoopDat#sctp_state{sctp_assoc_id = AssocId}); |
| |
| handle_info({sctp, Socket, RemoteIp, RemotePort, {[Anc], Data}}, State, LoopDat) -> |
| Module = LoopDat#sctp_state.module, |
| io:format("SCTP rx data: ~p ~p~n", [Anc, Data]), |
| % process incoming SCTP data |
| if Socket == LoopDat#sctp_state.sctp_sock, |
| RemoteIp == LoopDat#sctp_state.sctp_remote_ip, |
| RemotePort == LoopDat#sctp_state.sctp_remote_port -> |
| Ret = Module:rx_sctp(Anc, Data, State, LoopDat#sctp_state.ext_state), |
| case Ret of |
| {ok, Prim, ExtState} -> |
| send_prim_to_user(LoopDat, Prim); |
| {ignore, ExtState} -> |
| ok |
| end; |
| true -> |
| io:format("unknown SCTP: ~p ~p~n", [Anc, Data]), |
| ExtState = LoopDat#sctp_state.ext_state |
| end, |
| inet:setopts(Socket, [{active, once}]), |
| next_state(State, State, LoopDat#sctp_state{ext_state = ExtState}); |
| |
| handle_info({sctp, Socket, RemoteIp, RemotePort, {_Anc, Data}}, State, LoopDat) |
| when is_record(Data, sctp_shutdown_event) -> |
| io:format("SCTP remote ~p:~p shutdown~n", [RemoteIp, RemotePort]), |
| % FIXME: send SCTP_RELEASE.ind ? |
| inet:setopts(Socket, [{active, once}]), |
| case LoopDat#sctp_state.role of |
| active -> |
| reconnect_sctp(LoopDat); |
| _ -> |
| ok |
| end, |
| next_state(State, associating, LoopDat); |
| |
| handle_info(Info, State, LoopDat) -> |
| Module = LoopDat#sctp_state.module, |
| case Module:handle_info(Info, State, LoopDat#sctp_state.ext_state) of |
| {next_state, State, ExtState} -> |
| {next_state, State, LoopDat#sctp_state{ext_state = ExtState}} |
| end. |
| |
| |
| idle(#primitive{subsystem = 'M', gen_name = 'SCTP_ESTABLISH', spec_name = request}, LoopDat) -> |
| case LoopDat#sctp_state.role of |
| active -> |
| reconnect_sctp(LoopDat); |
| _ -> |
| ok |
| end, |
| next_state(idle, associating, LoopDat). |
| |
| |
| |
| associating(#primitive{subsystem = 'M', gen_name = 'SCTP_RELEASE', |
| spec_name = request}, LoopDat) -> |
| % directly send RELEASE.conf ?!? |
| next_state(associating, idle, LoopDat). |
| |
| |
| established(#primitive{subsystem = 'M', gen_name = 'SCTP_RELEASE', |
| spec_name = request}, LoopDat) -> |
| next_state(established, releasing, LoopDat); |
| established(#primitive{subsystem = 'MTP', gen_name = 'TRANSFER', |
| spec_name = request, parameters = Params}, LoopDat) -> |
| % MTP-TRANSFER.req from user app; Send message to remote peer |
| Module = LoopDat#sctp_state.module, |
| ExtState = Module:mtp_xfer(Params, LoopDat#sctp_state.ext_state), |
| next_state(established, established, LoopDat#sctp_state{ext_state = ExtState}); |
| established(#primitive{subsystem = 'SCTP', gen_name = 'TRANSFER', |
| spec_name = request, parameters = {Stream, Ppid, Data}}, LoopDat) -> |
| io:format("SCTP-TRANSFER.req~n",[]), |
| % somebody (typically callback module) requests us to send SCTP data |
| send_sctp_to_peer(LoopDat, Data, Stream, Ppid), |
| next_state(established, established, LoopDat). |
| |
| next_state(State, NewState, LoopDat) when is_record(LoopDat, sctp_state) -> |
| Module = LoopDat#sctp_state.module, |
| case NewState of |
| State -> |
| {next_state, NewState, LoopDat}; |
| _ -> |
| ExtState = Module:state_change(State, NewState, LoopDat#sctp_state.ext_state), |
| {next_state, NewState, LoopDat#sctp_state{ext_state = ExtState}} |
| end. |